Damping device for turbojet engine fan blades

Abstract

A damping device for the turbojet engine fan blades which includes a wedge placed between the platforms of the blades, the shanks of the blades, and the disc. The wedge consists of a hollow, bellows-shaped body fitted with an axial stop member, the body being inflated after mounting so that it takes up all the space between the platforms of the blades, the blade shanks and the teeth of the disc. The invention is used for damping device of turbojet engine blades.

What is claimed as new and desired to be secured by Letters Patent of the United States is: 
     
       1. A damping device for turbojet engine fan blades, each of said blades having a blade root portion, a half-platform and a shank interconnecting said root portion and said half-platform, comprising: a disc having a rim portion formed of a plurality of teeth delimiting axial grooves which receive said root portion of each of said blades, each of said blade root portions being extended radially by said shank connected to said half-platform and wherein each half-platform extends circumferentially on either side of said shank and wherein the half-platforms and the shank of two adjacent blades and each tooth of the disc form a space between said two adjacent blades; and   a wedge member mounted in said space and which further comprises a hollow, bellows-shaped body and means operatively associated with said wedge member for limiting axial movement of said wedge member, said body being inflated after mounting such that said body entirely occupies said space wherein said wedge member further comprises a first and second side which are interconnected on an upstream side of said blades wherein said first side is supported on end portions of the disc teeth and said second side is supported on said half-platforms of said adjacent blades and a folding wall interconnecting said first and second sides.   
     
     
       2. A damping device for turbojet engine fan blades, each of said blades having a blade root portion, a half-platform and a shank interconnecting said root portion and said half-platform, comprising: a disc having a rim portion formed of a plurality of teeth delimiting axial grooves which receive said root portion of each of said blades, each of said blade root portions being extended radially by said shank connected to said half-platform and wherein each half-platform extends circumferentially on either side of said shank and wherein the half-platforms and the shank of two adjacent blades and each tooth of the disc form a space between said two adjacent blades; and   a wedge member mounted in said space and which further comprises a hollow, bellows-shaped body and means operatively associated with said wedge member for limiting axial movement of said wedge member, said body being inflated after mounting such that said body entirely occupies said space wherein said means for stopping axial movement of said wedge member further comprises a first and second arm extending therefrom supported on a front face portion of said shank of each of said adjacent blades, respectively.   
     
     
       3. A system according to claim 2, wherein a front portion of said wedge has a cavity formed therein between said first and second arms and wherein said wedge further comprises an inflation valve mounted on said wedge within said cavity formed between the first and second arms. 
     
     
       4. A system according to claim 1, wherein said wedge further comprises a wedge of flexible, reinforced elastomeric material.